Users can now create sync rules to automatically sync events between
any two connected calendar providers (Google, Apple, Outlook, Synology).
- New Prisma models: CalendarSyncRule + CalendarSyncMapping
- Sync engine in src/lib/calendar-cross-sync.ts: fingerprint-based
change detection, anti-loop protection, one-way and two-way support
- API routes: GET/POST rules, PATCH/DELETE rule by id, POST run
- CalendarSyncRulesPanel component with rule list, add/edit form,
toggle enable/disable, Sync Now button with result summary
- New "Sync" tab in settings sidebar (between Connections and Account)
- Sync rules run automatically after each forced calendar cache refresh
v1.76.0